1. Technical Field
The present disclosure relates to a voltage boost circuit and a method of boosting voltage and, more particularly, to a voltage boost circuit and a method of boosting voltage using a voltage boost clock signal with varying frequency.
2. Discussion of Related Art
A voltage boosting circuit is a circuit that increases a voltage level of a received input voltage and outputs the increased voltage.
The level of boost voltage output by a general voltage boost circuit is proportional to a boost voltage frequency of a voltage boost clock signal and the amount of operational current of the voltage boost clock signal. In addition, the amount of load current flowing in a general voltage boost circuit is inversely proportional to the level of the boost voltage. Meanwhile, the amount of load current flowing in a general voltage boost circuit varies according to various conditions. In this case, in order for the voltage boost circuit to stably output a boost voltage over a predetermined target voltage, the voltage boost circuit should be able to output a boost voltage to the extent of the target voltage under a condition that the load current is at a maximum.
The boost voltage frequency of the voltage boost clock signal, however, is fixed in the voltage boost circuit. Therefore, in order for the voltage boost circuit to output boost voltage to the extent of the target voltage even under the condition that the load current is at a maximum, the voltage boost circuit fixes and outputs the highest boost voltage frequency that corresponds to the condition. Meanwhile, as described above, the amount of operational current of the voltage boost circuit is proportional to the boost voltage frequency. Therefore, under a condition other than the condition where the load current is at a maximum, the operational current of the voltage boost circuit may flow excessively.